Awesome, I love Piet! I wrote the "Alpha" example program on
http://www.dangermouse.net/esoteric/piet/samples.html as an exercise to learn Piet while solving Card #234 of Perplex City -
http://perplexcitycardcatalog.com/1/234/All of DM's esoteric languages are pretty interesting: http://www.dangermouse.net/esoteric/